欢迎访问《应用生态学报》官方网站,今天是 分享到:

应用生态学报 ›› 2012, Vol. 23 ›› Issue (03): 717-723.

• 研究论文 • 上一篇    下一篇

干旱胁迫下外源水杨酸对黄瓜幼苗膜脂过氧化和光合特性的影响

郝敬虹,易旸,尚庆茂**,董春娟,张志刚   

  1. 1中国农业科学院蔬菜花卉研究所/农业部园艺作物生物学与种质创新重点实验室, 北京 100081
  • 出版日期:2012-03-18 发布日期:2012-03-18

Effects of exogenous salicylic acid on  membrane lipid peroxidation and photosynthetic characteristics of
Cucumis sativus seedlings under drought stress.

HAO Jing-hong, YI Yang, SHANG Qing-mao, DONG Chun-juan, ZHANG Zhi-gang   

  1. Ministry of Agriculture Key Laboratory of Horticultural Crop Biology and Germplasm Innovation, Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, China
  • Online:2012-03-18 Published:2012-03-18

摘要: 为了探讨外源水杨酸(SA)提高植物抗旱性的相关机制,研究了干旱胁迫下(基质含水量为饱和持水量的60%和50%),根际施用外源SA对黄瓜幼苗生长、膜脂过氧化、脯氨酸积累、水分利用效率、净光合速率(Pn)和叶绿素荧光参数的影响.结果表明: SA处理能够缓解干旱胁迫对黄瓜幼苗生长、Pn和水分利用效率的抑制,减小膜脂过氧化程度,促进脯氨酸的积累;添加外源SA显著减小了干旱胁迫下黄瓜幼苗的PSⅡ最大光化学效率、PSⅡ实际光化学效率、PSⅡ潜在活性、PSⅡ有效光化学效率和光化学猝灭系数的下降幅度,抑制了非光化学猝灭系数的升高.添加外源SA可以缓解干旱胁迫造成的膜脂过氧化对膜系统的氧化损伤,并通过增强PSⅡ反应中心活性提高了Pn,有助于水分的利用,同时增大渗透调节能力,减少水分的散失,提高水分利用效率,从而增强植株对干旱的适应能力.

Abstract: To approach the related mechanisms of exogenous salicylic acid (SA) in improving plant drought-resistance, this paper studied the effects of applying exogenous SA to the rhizosphere on the plant growth, membrane lipid peroxidation, proline accumulation, water use efficiency, net photosynthetic rate (Pn), and chlorophyll fluorescence parameters of cucumber (Cucumis sativus) seedlings under drought stresses (60% and 50% of saturated water capacity). Applying SA relieved the inhibitory effects of drought stress on plant growth, Pn, and water use efficiency, decreased membrane lipid peroxidation, and promoted proline accumulation. Meanwhile, the SA decreased the decrements of the maximum photochemical efficiency of PSⅡ, actual photochemical efficiency of PSⅡ, potential activity of
PSⅡ, effective photochemical efficiency of PSⅡ, and photochemical quenching coefficient  under drought stress significantly, and limited the increase of non-photochemical quenching coefficient. All the results suggested that applying exogenous SA could alleviate the oxidation damage of cell membrane resulted from the drought-caused membrane lipid peroxidation, improve the Pn by increasing
PSⅡ activity to benefit water utilization, enhance the regulation capability of osmosis to decrease water loss and increase water use efficiency, and thereby, improve the plant drought-resistance.